jquery set visibility

An even simpler way to do this is to use jQuery's toggleClass() method

CSS
.newClass{visibility: hidden}

HTML
<a href="#" class=trigger>Trigger Element </a>
<div class="hidden_element">Some Content</div>

JS
$(document).ready(function(){
    $(".trigger").click(function(){
        $(".hidden_element").toggleClass("newClass");
    });
});